I have seen one and know someone that has one. It is close to 600 lumens, and the beam pattern is ok. The all in one design is nice, however the runtime is pretty short on high, and the cost is very high! You can get one of the nicer chinese lights (the Titans) for a 3rd the cost, with a longer runtime, and lighter weight. The batteries can mount on the stem in most cases.

For the money you save buy going that route over the Cygo, you could also purchase a helmet light, and have money for a weeks worth of gas...

I can't comment on the 600, but I've been running a TridenX LED Li-Ion Xtra 600 for two years now and it's still going strong. Couple of decent get-offs and it's still good. I use it 3-4 times a week once the temps are above about 90 or so during the year, so I've got alot of hours on it. I'm very satisfied with it to where I'm keeping an eye on the Centauri 1000 for next summer...